Light-emitting device and lighting device
The light-emitting device addresses peeling and yellow ring issues by using a reflective resin layer more prone to hardening and shrinking, with recesses and thickness adjustments, enhancing stability and light extraction efficiency.
Patent Information
- Application Number
- JP2024116302
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-07-19
- Publication Date
- 2026-01-29
AI Technical Summary
Conventional light emitting devices suffer from insufficient light emitting characteristics, including the occurrence of yellow rings and peeling of the phosphor resin layer.
A light-emitting device design featuring a light-emitting element mounted on a substrate, surrounded by a resin wall, with a reflective resin layer between the resin wall and the element, and a phosphor resin layer above, where the reflective resin layer is more susceptible to hardening and shrinking than the phosphor resin layer, and includes recesses and thickness adjustments to enhance stability and light reflection.
The design effectively suppresses peeling of the phosphor resin layer, improves light extraction efficiency, and reduces yellow ring light output, resulting in stable light-emitting characteristics.
Smart Images

Figure 2026014832000001_ABST
Abstract
Description
[Technical Field]
[0001] The present disclosure relates to a light emitting device and an illumination device. [Background technology]
[0002] Conventionally, a light emitting device has been known in which a light emitting element and a reflective resin are stacked inside an opening in a resin wall formed on a substrate, with a phosphor layer covering them (Patent Documents 1 and 2).By using a resin layer such as a reflective resin around the light emitting element, the light extraction efficiency is improved. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] Japanese Patent Application Publication No. 05-029665 [Patent Document 2] Japanese Patent Application Laid-Open No. 2004-055632 Summary of the Invention [Problem to be solved by the invention]
[0004] The light emitting devices described in Patent Documents 1 and 2 above have had the problem that they do not provide sufficient light emitting characteristics, such as the occurrence of yellow rings.
[0005] The present disclosure has been made to solve the above problems, and aims to provide a light-emitting device with improved light-emitting characteristics, and an illumination device including the same. [Means for solving the problem]
[0006] The present disclosure has been made to achieve the above-mentioned object, and provides a light-emitting device that includes a light-emitting element mounted on a substrate, a resin wall surrounding the light-emitting element, a reflective resin layer provided on the substrate between the resin wall and the light-emitting element, and a phosphor resin layer provided above the light-emitting element, wherein the reflective resin layer is made of a material that is more susceptible to hardening and shrinking due to heat than the phosphor resin layer.
[0007] Such a light emitting device can improve the light emitting characteristics.
[0008] In this case, the light-emitting element includes a light-emitting layer that generates light inside, and the upper surface of the reflective resin layer on the light-emitting element side is higher than the upper surface of the light-emitting layer and lower than the upper surface of the light-emitting element, and a recess is provided on the upper surface of the reflective resin layer between the light-emitting element and the resin wall.
[0009] This allows the reflective resin layer to effectively reflect light emitted from the sides of the light-emitting layer of the light-emitting element.Furthermore, the thickness of the reflective resin layer can reduce the amount of light emitted obliquely downward from the light-emitting layer that leaks through to the back side of the substrate.
[0010] In this case, the phosphor resin layer may be provided within and above the recess in the upper surface of the reflective resin layer, and a depression may be provided in the upper surface of the phosphor resin layer corresponding to the recess in the upper surface of the reflective resin layer.
[0011] This allows a portion of the phosphor resin layer to enter the recess, further enhancing the effect of suppressing and reducing peeling of the reflective resin layer. Also, it is possible to suppress the output of yellow ring light from the depressions on the upper surface of the phosphor resin layer that correspond to the recesses on the upper surface of the reflective resin layer.
[0012] In this case, the device may include a plurality of the light-emitting elements mounted on the substrate at a distance from each other, a second reflective resin layer provided on the substrate between the light-emitting elements, and a second phosphor resin layer provided above the second reflective resin layer, the second reflective resin layer being made of a material that is more susceptible to hardening and shrinking due to heat than the second phosphor resin layer, and a second recess being provided on the upper surface of the second reflective resin layer.
[0013] This makes it possible to more effectively prevent or reduce peeling of the phosphor resin layer.
[0014] In this case, the resin wall has an upper portion whose opening dimension widens upward and a lower portion whose opening dimension widens downward, and the reflective resin layer can be configured within a height range from the height of the upper portion on the resin wall side to the height of the lower portion on the resin wall side.
[0015] This makes it possible to more effectively reduce peeling of the reflective resin layer.
[0016] In this case, the reflective resin layer may be made of a resin that is softer than the phosphor resin layer.
[0017] This makes it possible to more effectively suppress or reduce peeling of the reflective resin layer.
[0018] In this case, the light-emitting element includes a light-emitting layer that generates light inside and has a flip-chip structure, and the upper surface of the reflective resin layer can be higher than the upper surface of the light-emitting layer and lower than the upper surface of the light-emitting element.
[0019] This allows the reflective resin layer to effectively reflect light emitted from the side of the light emitting layer of the light emitting element having a flip-chip structure.
[0020] In this case, the light emitting device can be provided as a lighting device.
[0021] This makes it possible to provide a lighting device with stable light-emitting characteristics. [Effects of the Invention]
[0022] As described above, according to the light emitting device of the present disclosure, peeling of the phosphor resin layer can be easily suppressed or reduced. [Brief explanation of the drawings]
[0023] [Figure 1] 1 shows an example of a light emitting device according to the present disclosure (cross-sectional view). [Figure 2] 10 is a cross-sectional view showing another example (modification 1) of the light emitting device according to the present disclosure. [Figure 3] 10 is a cross-sectional view showing another example (modification 2) of the light emitting device according to the present disclosure. [Figure 4] 10 is a cross-sectional view showing another example (third modification) of the light emitting device according to the present disclosure. [Figure 5] 1 shows an example of an illumination device according to the present disclosure (top view). [Figure 6] 1 shows an example of a light emitting device according to a conventional example (cross-sectional view). DETAILED DESCRIPTION OF THE INVENTION
[0024] The present disclosure will be described in detail below, but the present disclosure is not limited thereto.
[0025] As described above, there has been a demand for a light emitting device that can suppress or reduce peeling of the phosphor oil layer from the substrate.
[0026] As a result of extensive research into the above-mentioned problems, the inventors have discovered that the light-emitting characteristics can be improved by a light-emitting device comprising a light-emitting element mounted on a substrate, a resin wall surrounding the light-emitting element, a reflective resin layer provided on the substrate between the resin wall and the light-emitting element, and a phosphor resin layer provided above the light-emitting element, wherein the reflective resin layer is made of a material that is more susceptible to thermal hardening and shrinkage than the phosphor resin layer, and have completed the present disclosure.
[0027] The following description will be made with reference to the drawings.
[0028] [Light-emitting device] First, a light-emitting device according to the present disclosure will be described with reference to FIGS. 1-3 (cross-sectional views). As shown in FIGS. 1-3, light-emitting devices 100, 200, and 300 according to the present disclosure include a light-emitting element 2 mounted on a substrate 1 and a resin wall 4 having an opening surrounding the light-emitting element 2. The resin wall 4 includes an opening reduction portion 5 in which the opening dimension of the opening is reduced in the normal direction to the upper surface of the substrate 1. A reflective resin layer 7 is provided on the upper surface of the substrate 1 between the opening reduction portion 5 of the resin wall 4 and the light-emitting element 2. Furthermore, a phosphor resin layer 9 is provided above the light-emitting element 2, above the reflective resin layer 7, and above the resin wall 4.
[0029] In the light-emitting devices 100, 200, and 300 shown in FIGS. 1-3 , the resin wall 4 includes an aperture reduction portion 5. Furthermore, the reflective resin layer 7 fills the space between the aperture reduction portion 5 and the substrate 1. This creates an anchor effect in the portion of the reflective resin layer 7 provided on the upper surface of the substrate 1 between the aperture reduction portion 5 and the light-emitting element 2, thereby easily preventing or reducing peeling of the reflective resin layer 7. This results in a light-emitting device in which the reflective resin layer 7 is stably disposed on the substrate 1. Furthermore, the resin wall 4 includes an aperture reduction portion 5, which increases the tendency of the reflective resin layer 7 to creep up onto the resin wall 4, thereby improving the light extraction efficiency through reflection. Furthermore, compared to the resin wall structure described in Patent Documents 1 and 2, in which the aperture dimension simply expands in the normal direction (upward) of the upper surface of the substrate 1, the resin wall can be increased in height while keeping its width small. This allows for a lower phosphor concentration in the phosphor resin layer, contributing to cost reduction.
[0030] 1-3, a light emitting device may be provided with a semiconductor element without a light emitting layer, such as a Zener diode 30, on the upper surface of the substrate 1 within the opening in the resin wall 4, as shown in Fig. 4. This type of reflective resin layer also serves as a sealing resin that prevents the intrusion of moisture from the outside and prevents scratches caused by contact from the outside.
[0031] (substrate) In the light emitting device according to the present disclosure, the type of substrate 1 is not particularly limited, but it is preferable to use, for example, a ceramic substrate. The ceramic substrate has a small linear expansion coefficient among other practical substrates, and the temperature characteristics of the ceramic substrate are close to those of the resin such as the reflective resin layer 7 provided on the substrate 1, so the temperature characteristics of the entire light emitting device become more stable and improved.
[0032] (light-emitting element) In the light emitting device according to the present disclosure, the type of the light emitting element 2 is not particularly limited. The light emitting element 2 can be selected from well-known LED chips that output ultraviolet to blue light, or may be an LED chip that outputs red light. The light emitting element 2 may have electrodes 13 and 14 bonded to a metal pattern 11 provided on a substrate 1 via a bonding layer 12 such as solder. As the light emitting element (LED chip), it is desirable to use a flip chip that has a P-type electrode and an N-type electrode on one main surface and emits light from the other main surface. In the LED chip, light is output from the light emitting layer 3, but it is also possible to use an LED chip that emits light not only from above or below the LED chip, but also from above or below the LED chip. In addition, light is output from the sides (side faces) as well. When a flip chip is used, the base portion of the LED chip (the upper surface side of the light-emitting element (LED chip) 2) becomes the light extraction surface side, so it is relatively easy to ensure the distance in the thickness direction from the light-emitting layer 3 to the light extraction surface. As a result, even if the reflective resin layer 7 is provided up to a height between the side face of the light-emitting layer 3 and the upper surface of the LED chip 2, the problem of the reflective resin layer 7 climbing up onto the light extraction surface is unlikely to occur. Therefore, the light extraction efficiency of the light-emitting device can be stably increased.
[0033] Furthermore, the number of light-emitting elements 2 to be placed inside the openings of the resin wall 4 is not particularly limited. One light-emitting element 2 may be placed in one opening. A buffer film (not shown) that reduces total reflection of light from the side surface of the light-emitting layer 3 may be provided between the reflective resin layer 7 and the light-emitting element 2. Furthermore, something other than the reflective resin layer 7 may be provided between the reflective resin layer 7 and the resin wall 4, between the reflective resin layer 7 and the substrate 1, and / or between the reflective resin layer 7 and the phosphor resin layer 9.
[0034] (Resin wall) The resin wall 4 is formed on the substrate 1 so as to surround the light-emitting element 2, forming an opening. The light-emitting element 2, the reflective resin layer 7, the phosphor resin layer 9, etc. are arranged inside the opening of the resin wall 4. The resin wall 4 is also called a dam or a resin frame. As described above, the resin wall 4 may be any wall that includes an opening reduction portion 5. The opening reduction portion 5 of the resin wall 4 reduces the opening dimension of the opening in the normal direction to the upper surface of the substrate 1. The opening reduction portion 5 can also be said to have a shape that overhangs toward the opening side surrounded by the resin wall 4 when the resin wall 4 is viewed in cross section.
[0035] The resin wall 4 can be made of a resin containing a filler such as titanium oxide that enhances light reflection. As long as the light-emitting element 2, the reflective resin layer 7, the phosphor resin layer 9, etc. can be arranged in the opening of the resin wall 4, the shape and constituent materials of the resin wall 4 other than the opening reduction portion 5 are not particularly limited.
[0036] As mentioned above, it is preferable to use a ceramic substrate with high thermal conductivity as substrate 1, but since the ceramic substrate does not have a light-reflecting resist (light-reflective solder resist) applied to its surface, light emitted downward from light-emitting element 2 is likely to transmit to the back surface of substrate 1. When using a ceramic substrate that allows light to easily pass through (leak) to the back side of the substrate 1, thickening the reflective resin layer 8 can suppress light leakage to the back side of the substrate 1 and improve luminous flux. To support the thick reflective resin layer 8, the resin wall 4 also needs to be relatively high. However, by providing the opening reduction portion 5 in the resin wall 4 as in the present disclosure, the height (H) of the resin wall 4 can be easily ensured without increasing the width (W) of the resin wall 4 in FIG. 1, and a thick reflective resin layer 8 can be easily and stably formed. This makes it possible to provide a light-emitting device that can more effectively suppress light leakage to the back side of the substrate 1.
[0037] Furthermore, when using a light-emitting element (LED chip) with a flip-chip structure as described above, it is necessary to provide a metal pattern 11 printed on the substrate 1. However, since the metal pattern 11 absorbs light, if it becomes possible to provide a thick reflective resin layer 7 on the metal pattern 11, it is expected that the light absorption by the metal pattern 11 will be reduced.
[0038] The shape of the side opposite to the opening (outside) when viewing the resin wall 4 in cross section is not particularly limited. It may be asymmetrical with the opening side (inside), for example, may be perpendicular to the upper surface of the substrate, or may have the same cross-sectional shape as the opening side (inside).
[0039] 1-3, an opening expansion section 6 may be provided above the opening reduction section 5, which expands the opening dimensions in the direction normal to the upper surface of the substrate 1 in a cross-sectional view. In such cases, the cross-sectional shape of the resin wall 4 is preferably a polygonal shape, such as a substantially circular, elliptical, diamond, hexagonal, or octagonal shape, because this facilitates the formation of the resin wall. Here, the term "substantially" includes a cross-sectional shape that is slightly distorted or partially rounded. The cross-sectional shape of the resin wall 4 can be adjusted by adjusting the shape of the nozzle used to extrude the resin to form the resin wall 4 to match the cross-sectional shape of the resin wall 4 to be formed. By providing the opening expansion section 6 above the opening reduction section 5, the width of the resin wall 4 can be made relatively narrow and the height of the resin wall 4 can be made relatively high. This allows the resin wall 4 to be provided with a thick reflective resin layer 7 while keeping the size of the light-emitting device relatively small.
[0040] As shown in the conventional light-emitting device 400 in Figure 6, if the resin wall 4 is composed only of an opening expansion section 6 in which the opening dimension of the opening expands in the normal direction to the upper surface of the substrate 1 in a cross-sectional view, or if it is a vertical wall in which the opening dimension of the opening is constant, the anchor effect does not act on the reflective resin layer 7, and the reflective resin layer 7 becomes prone to peeling off from the substrate 1.
[0041] The shape of the opening of the resin wall 4 in the plan view of the light emitting device is not particularly limited, and examples include a polygon including a rectangle, a circle, etc. If the resin wall has a rectangular shape in the plan view as in the example of the lighting device 500 in Fig. 5, it is possible to effectively suppress variations in the in-plane distribution as a surface light source when used as a light source for a lamp such as a fog lamp.
[0042] (Reflective resin layer) The reflective resin layer 7 is provided in the space of the opening of the resin wall 4 on the upper surface of the substrate 1 (inside the area surrounded by the resin wall 4), and is also arranged around the light-emitting element 2. As shown in FIG. 1-3 , when multiple light-emitting elements 2 are provided in the space of the opening of the resin wall 4, the reflective resin layer 7 is also provided between the light-emitting elements 2. The reflective resin layer 7 may also be provided between the metal pattern 11 on the substrate 1 and the electrodes 13 and 14 of the light-emitting element 2. The opening reduction portion 5 provided in the resin wall 4 acts as an anchor for the reflective resin layer 7, suppressing and reducing peeling of the reflective resin layer 7 from the substrate 1. The reflective resin layer 7 according to the present disclosure is intended to reflect light from the light emitting element 2 and efficiently guide the light upward, thereby improving light extraction efficiency, and is made of a resin containing a filler such as titanium oxide that enhances light reflection.
[0043] As shown in Figures 1-3, a flip-chip structure light-emitting element 2 is preferably used, in which the reflective resin layer 7 and the light-emitting element 2 are in contact with each other. Furthermore, by increasing the thickness of the reflective resin layer 7 and reflecting light upward while reducing light leakage to the backside of the substrate 1, the brightness of the light-emitting device can be further improved. In particular, it is more preferable to form the reflective resin layer 7 with a thickness such that the upper surface 7S of the reflective resin layer 7 is higher than the height of the upper surface 3S of the light-emitting layer 3 of the light-emitting element 2 but lower than the height of the upper surface 2S of the light-emitting element 2. This allows the reflective resin to reflect light emitted from the lateral (side) surfaces of the light-emitting layer 3. Therefore, the brightness of the light-emitting device can be further improved. Furthermore, the portion of the reflective resin layer 7 on the light-emitting element 2 side is preferably provided above the side surface of the light-emitting layer 3 to a height between the upper surface of the LED chip 2 and the upper surface of the LED chip 2. Furthermore, the portion of the reflective resin layer 7 on the resin wall 4 side is preferably provided from the height of at least a portion of the opening reduction portion 5 of the resin wall 4 to the height of at least a portion of the opening expansion portion 6 of the resin wall 4. This creates an anchor effect, which stably prevents peeling of the reflective resin layer 7, while reflecting light from the light-emitting element 2 and efficiently directing the light upward, more effectively preventing light leakage to the back side of the substrate 1.
[0044] 1-3, it is preferable that the resin wall 4 has the above-mentioned enlarged opening portion 6, and the reflective resin layer 7 extends from the reduced opening portion 5 to the enlarged opening portion 6. In this case, peeling of the reflective resin layer 7 can be more effectively suppressed and reduced.
[0045] Examples of resins that form the reflective resin layer 7 include silicone resins and hybrid resins that have the properties of both silicone resins and epoxy resins.
[0046] In addition, since the ceramic substrate does not have a light-reflecting resist (light-reflective solder resist) applied to its surface, light emitted downward from the light-emitting element 2 easily passes through to the back surface of the substrate 1. Therefore, it is preferable to provide the reflective resin layer 7 not only on the side surface of the light-emitting layer 3 of the light-emitting element 2 but also on the front surface side of the substrate 1 below the side surface of the light-emitting layer 3, thereby increasing the thickness of the resin in the reflective resin layer 7 and suppressing light leakage to the back surface side of the substrate 1. This makes it possible to provide a light-emitting device that has good temperature characteristics while more effectively suppressing light leakage to the back surface side of the substrate 1.
[0047] Furthermore, when using a light emitting element (LED chip) 2 with a flip-chip structure as described below, it is necessary to provide a metal pattern 11 printed on the substrate 1. However, since the metal pattern 11 absorbs light, if it becomes possible to provide a thick reflective resin layer 7 on the metal pattern 11, it can be expected that the reflective resin layer 7 will reduce light absorption by the metal pattern 11.
[0048] (phosphor resin layer) The resin of the phosphor resin layer 9 according to the present disclosure is not particularly limited as long as it is made of a resin containing a phosphor. Examples of resins constituting the phosphor resin layer 9 include silicone resins and hybrid resins having the properties of both silicone resins and epoxy resins. The resin of the phosphor resin layer 9 may have a Shore A hardness of 15 to 35, for example. The phosphor may contain one or more types of phosphors, such as a YAG phosphor.
[0049] The phosphor resin layer 9 is provided above the light-emitting element 2 and above the reflective resin layer 7 between the light-emitting element 2 and the resin wall 4, and it is sufficient that it covers at least the output surface of the light-emitting element. When multiple light-emitting elements 2 are provided in the space of an opening in the resin wall 4 as shown in FIG. 1-3, the phosphor resin layer 9 may be provided above the reflective resin layer 7 between the light-emitting elements 2. As shown in FIG. 1-3, the phosphor resin layer 9 may be formed so as to cover the entire opening of the resin wall 4. Furthermore, as shown in FIGS. 1 to 3, the phosphor resin layer 9 may be in contact with the top of the opening expansion portion 6, or may be provided inside the opening expansion portion 6.
[0050] A preferred embodiment of the relationship between the resin wall, the reflective resin layer, and the phosphor resin layer will now be described.
[0051] The resin of the phosphor resin layer 9 preferably satisfies a predetermined relationship of softness with the resin of the reflective resin layer .
[0052] The reflective resin layer 7 may be made of a resin that is softer than the phosphor resin layer 9. In the present disclosure, the softness of the resin may be defined by Shore A hardness. In this case, the reflective resin layer 7 being softer than the phosphor resin layer 9 means that the resin of the reflective resin layer 7 has a lower Shore A hardness than the resin of the phosphor resin layer 9. The softness of the resin of the reflective resin layer 7 may be, for example, in the range of 17 to 26 in Shore A hardness, and more preferably 20. The softness of the resin of the phosphor resin layer 9 may be, for example, 26 in Shore A hardness. The base resin of the reflective resin layer 7 may be the same type of resin as the resin that constitutes the phosphor resin layer 9, and may be selected from resins with different specifications of softness (Shore A hardness).
[0053] The reflective resin layer 7 improves light extraction efficiency by covering the side surfaces of the light emitting element 2, and by using a soft resin, it is possible to absorb the effects of thermal expansion and contraction caused by the heat generated by the light emitting element 2. Such a light emitting device is capable of suppressing changes in light emitting characteristics caused by heat generated by the light emitting element.
[0054] If the resin of the reflective resin layer 7 is harder than the resin of the phosphor resin layer 9 (the Shore A hardness of the phosphor resin layer 9 is << the reflective resin layer 7), when the light-emitting element 2 reaches a high temperature, heat is transferred to the reflective resin layer 7, and the reflective resin layer 7, which is surrounded by the resin wall 4 and the substrate 1, tends to expand mainly toward the phosphor resin layer 9. At this time, if the hardness of the phosphor resin layer 9 is high, internal stress in the reflective resin layer 7 increases. As a result, peeling may occur at the interface between the reflective resin layer 7 and the light-emitting element 2, starting from the corners or sides of the light-emitting element 2, resulting in a decrease in the light extraction efficiency of the light-emitting device and a bias in the chromaticity distribution. If the difference in Shore A hardness between the resins of the reflective resin layer 7 and the phosphor resin layer 9 is small, or more preferably, is approximately the same, the phosphor resin layer 9 can deform to follow the deformation of the reflective resin layer 7 when the reflective resin layer 7 tries to expand toward the phosphor resin layer 9. As a result, it is possible to prevent peeling from occurring at the interface between the reflective resin layer 7 and the light-emitting element 2, starting from the corners or sides of the light-emitting element 2. Therefore, it is preferable that the difference in Shore A hardness between the resin of the reflective resin layer 7 and the resin of the phosphor resin layer 9 is small, and more preferably, they are about the same. It is preferable that the difference in Shore A hardness between the resin of the reflective resin layer 7 and the resin of the phosphor resin layer 9 (Shore A hardness of the phosphor resin layer - Shore A hardness of the reflective resin layer) is 0 or more and 20 or less, more preferably 0 or more and 18 or less.
[0055] Furthermore, it is also preferable that the resin of the reflective resin layer 7 is made of a material that is more susceptible to thermal cure and shrinkage than the resin of the phosphor resin layer 9. The ease of cure and shrinkage in this case can be expressed, for example, by the shrinkage rate at the time of curing, and it is preferable that the shrinkage rate of the resin of the reflective resin layer 7 is greater than that of the phosphor resin layer 9. By using such a combination of resins, a recess (depression) 8 is formed in the upper surface of the reflective resin layer 7, as shown in the light emitting device 200 of FIG. 2 and the light emitting device 300 of FIG. 3.
[0056] As shown in Figures 2 and 3, the upper surface of the reflective resin layer 7 in contact with the side surface of the light-emitting element 2 is formed so as to be higher than the upper surface 3S of the light-emitting layer 3 and lower than the upper surface 2S of the light-emitting element 2. A recess 8 is formed on the upper surface of the reflective resin layer 7 between the light-emitting element 2 and the resin wall 4. A portion of the phosphor resin layer 9 is embedded in the recess 8. This allows the reflective resin layer 7 to effectively reflect light emitted from the side of the light-emitting layer 3, thereby improving the brightness of the light-emitting device. Furthermore, by providing a relatively thick reflective resin layer 7, the bonding area with other components increases, further reducing peeling of the reflective resin layer 7. Furthermore, having a portion of the phosphor resin layer 9 embedded in the recess 8 further enhances the effect of suppressing and reducing peeling of the reflective resin layer 7. Furthermore, the thickness of the reflective resin layer 7 reduces the light emitted obliquely downward from the light-emitting layer 3 from leaking through to the back surface of the substrate 1.
[0057] Furthermore, by forming the recesses (depressions) 8 on the upper surface of the reflective resin layer 7 so as to be continuous with the enlarged opening portions 6 of the resin wall 4, the recesses (depressions) 8 between the light-emitting element 2 and the resin wall 4 are rounded, which effectively suppresses deterioration of the light-emitting characteristics, such as the light emitted from the light-emitting element 2 becoming cross light and being less likely to produce a yellow ring, thereby improving the light-emitting characteristics. Thus, it is preferable that the reflective resin layer 7 has recesses (depressions) 8 on its upper surface. Furthermore, by having a portion of the phosphor resin layer 9 embedded in the recesses 8, peeling of the reflective resin layer 7 is more effectively reduced and suppressed. Furthermore, when recesses (depressions) 8 on the upper surface of the reflective resin layer 7 are provided between the light-emitting elements 2 as shown in FIG. 2 and the phosphor resin layer 9 thereon is thick, it is possible to suppress the intensification of the light output above the recesses (depressions) 8.
[0058] When a recess (depression) 8 is formed on the upper surface of the reflective resin layer 7, a recess (depression) 10 may also be formed on the surface of the phosphor resin layer 9 above the recess of the reflective resin layer 7, as shown in the light-emitting device 300 of FIG. 3. This structure is more preferable because it further improves the angular color difference. By relatively increasing the adhesion with the reflective resin layer 7, a recess (depression) 10 is also more likely to be formed on the surface of the phosphor resin layer 9. In particular, when a recess (depression) 8 is provided on the upper surface of the reflective resin layer 7 between the light-emitting elements 2 as shown in FIG. 3 and a recess (depression) 10 is also provided on the surface of the phosphor resin layer 9, the angular color difference can be further improved compared to when no recess (depression) 10 is provided.
[0059] The resin walls 4 are preferably made of a resin harder than the phosphor resin layer 9 (the resin of the phosphor resin layer 9 is softer than the resin of the resin walls 4). In this case, a resin having a Shore A hardness of 53 to 68 can be used as the resin constituting the resin walls 4. Furthermore, the difference in Shore A hardness between the resin of the resin walls 4 and the resin of the reflective resin layer 7 is preferably 25 or more, more preferably 35 or more.
[0060] (Lighting equipment) The present disclosure can provide a lighting device including the above-described light-emitting device. FIG. 6 shows an example of a lighting device (top view). Note that the phosphor resin layer is not shown so that components such as the light-emitting element can be seen. It is possible to provide a light-emitting device including a Zener diode 30 and the like in addition to the light-emitting element 2 within an opening in a resin wall 4 provided on a substrate 1, and a lighting device 500 including a diode 31 and an IC 32 on the substrate 1 outside the opening in the resin wall 4. Specific uses of the lighting device are not particularly limited, and it can be used as indoor lighting, outdoor lighting, a headlamp for an automobile, etc.
[0061] As described above, the light emitting device of the present disclosure is a light emitting device that can improve the light emitting characteristics.
[0062] The present disclosure is not limited to the above-described embodiments. The above-described embodiments are merely examples, and any configuration that is substantially identical to the technical idea described in the claims of the present disclosure and that provides similar effects is included within the technical scope of the present disclosure. [Explanation of symbols]
[0063] 1...substrate, 2...light-emitting element, 2S...upper surface of light-emitting element, 3...light-emitting layer, 3S...upper surface of light-emitting layer, 4...resin wall, 5...reduced opening portion, 6...enlarged opening portion, 7...Reflective resin layer, 7S...Upper surface of reflective resin layer, 8...Concave portion (reflective resin layer), 9...phosphor resin layer, 10...recess (phosphor resin layer), 11...metal pattern, 12... junction layer; 13, 14... electrodes; 30... Zener diode; 31...Diode, 32...IC, 100, 200, 300, 400...light-emitting devices, 500...lighting devices.
Claims
1. a light emitting element mounted on a substrate; a resin wall surrounding the light-emitting element; a reflective resin layer provided on the substrate between the resin wall and the light-emitting element; a phosphor resin layer provided above the light-emitting element, The light emitting device is characterized in that the reflective resin layer is made of a material that is more susceptible to shrinkage due to hardening caused by heat than the phosphor resin layer.
2. The light-emitting device includes a light-emitting layer therein that generates light, an upper surface of the reflective resin layer on the light-emitting element side is higher than an upper surface of the light-emitting layer and lower than an upper surface of the light-emitting element; 2. The light emitting device according to claim 1, wherein a recess is provided on the upper surface of the reflective resin layer between the light emitting element and the resin wall.
3. The phosphor resin layer is provided in and above the recessed portion on the upper surface of the reflective resin layer, 3. The light emitting device according to claim 2, wherein the phosphor resin layer has an upper surface provided with a depression corresponding to the recess in the upper surface of the reflective resin layer.
4. a plurality of the light-emitting elements mounted on the substrate at a distance from each other; a second reflective resin layer provided on the substrate between the light-emitting elements; a second phosphor resin layer provided above the second reflective resin layer, the second reflective resin layer is made of a material that is more susceptible to thermal hardening and shrinkage than the second phosphor resin layer; 3. The light emitting device according to claim 2, wherein a second recess is provided on the upper surface of the second reflective resin layer.
5. the resin wall has an upper portion whose opening dimension increases upward and a lower portion whose opening dimension increases downward, A light-emitting device described in any one of claims 1 to 4, characterized in that the reflective resin layer is configured within a height range from the height of the upper part on the resin wall side to the height of the lower part on the resin wall side.
6. 2. The light emitting device according to claim 1, wherein the reflective resin layer is made of a resin softer than the phosphor resin layer.
7. The light emitting device includes a light emitting layer that generates light therein and has a flip-chip structure, 2. The light emitting device according to claim 1, wherein an upper surface of the reflective resin layer is higher than an upper surface of the light emitting layer and lower than an upper surface of the light emitting element.
8. A lighting device comprising the light-emitting device according to any one of claims 1 to 7.
Citation Information
Patent Citations
LED light source device
JP1993029665A
Semiconductor light-emitting device
JP2004055632A